Rinse the leeks carefully before removing the tops and bottoms, then cut the leeks lengthwise and look for any additional silt. If you see a bit of dirt inside of the leek, just gently rinse it out before slicing the leeks crosswise into small strips.

Rinse and dry the mushrooms and then pop out the caps before slicing the caps of the mushrooms.

In a medium sized pot, sauté the leeks in the water, over medium heat, for five minutes.

Add the mushrooms, milk, broth, and coriander, adjust the heat to medium-high, and allow the soup to come to a gentle boil.

Boil the soup for three minutes before removing it from the heat.

Salt and pepper to taste and serve immediately.